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71.
Kenji Miyatake Mitsutoshi Jikei Junya Katoh Kimihisa Yamamoto Hiroyuki Nishide Eishun Tsuchida 《先进技术聚合物》1994,5(4):216-220
Poly(2,5-dimethylphenylene sulfide) was prepared by oxidative polymerization of sulfur chloride with p-xylene using 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) as an oxidizing agent. The reaction proceeded efficiently under atmospheric pressure and at room temperature. The polymer formed had a high melting temperature and linear structure which was confirmed by spectroscopies. The effects of reaction time, solvent, temperature and oxidizing agent on polymerization are also discussed. 相似文献
72.
The hexamolybdenum cluster complex [Mo6(3-Cl)8(O2CMe)6]2–, 1 was isolated as the Bu4N+ salt in 71% yield from the reaction of (Bu4N)2[Mo6(3-Cl)8Cl6] with AgO2CMe in CH2Cl2 solvent. The compound was characterized by single crystal X-ray diffraction analysis. The cluster contains an octahedral arrangement of six molybdenum atoms with eight chloride ligands bridging the eight trianglar faces and six carboxylate ligands terminally coordinated through one oxygen atom to each of the six molybdenum atoms. Crystal data: space group =P21/n,a=10.713(3)Å,b=14.43(1)Å,c=21.919(4)Å, =94.37(2)°,Z=2, 1965 reflections,R=0.036. 相似文献
73.
74.
The crystal structures of molybdocene‐amino acid compounds of the type [Cp2MoIV(κN, κO‐AA)]+Cl—·xH2O with AA = D ‐phenylalaninato (x = 1.5), DL ‐leucinato (x = 2) and DL ‐valinato (x = 1) have been determined (Cp = η5‐C5H5). The compounds feature an almost planar, five‐membered chelate ring of the aminocarboxylate moiety (deprotonated amino acid) with the molybdenum atom. In the phenylalaninato complex π‐stacking between the phenyl rings is found. The complexes were proven kinetically stable at pH < 1 for at least 24 h. 相似文献
75.
Semiconductor–semiconductor and molecule (molecular ion)–semiconductor products are formed upon the implantation of Ag+, Cu+, and Cu2+ ions in the CdS surface. Possible mechanisms were examined for their photocatalytic action in the reduction of methylene blue. 相似文献
76.
Alistair J Usher Nigel T Lucas Simon Petrie Mark G Humphrey Anthony C Willis 《Journal of organometallic chemistry》2004,689(1):50-57
Reaction of WH(CO)3(η-C5Me5) with IrCl(CO)2(4-H2NC6H4Me) affords WIr3(μ-CO)3(CO)8(η-C5Me5) in low yield. A structural study reveals a WIr2-centred plane of bridging carbonyls, in contrast to the crystal structure of WIr3(CO)11(η-C5H5) (all-terminal carbonyl distribution). DFT calculations reveal an increasing proclivity to adopt an all-terminal CO disposition for clusters MIr3(CO)11(η-C5H5) in the gas phase on proceeding from M=Cr to Mo and then W, consistent with structural studies in the solid state for which the tungsten-containing cluster is the only all-terminal example. Increasing electron donation from the ligands in the tungsten system (either from phosphine substitution or cyclopentadienyl permethylation) suffices to impose a plane of bridging carbonyls in the ground state structure. 13C NMR fluxionality studies reveal that CO exchange mechanism(s) for WIr3(CO)11(η-C5H5) and the related tetrahedral cluster W2Ir2(CO)10(η-C5H5)2 are very fast and involve all carbonyls on the clusters. DFT calculations on MIr3(CO)11(η-C5H5) (M=Cr, Mo) substantiate a ‘merry-go-round’ mechanism for carbonyl scrambling in these systems, a result which is consistent with the scrambling behaviour seen in the NMR fluxionality studies on the W-containing congener. 相似文献
77.
F. Sanem Koçak 《Journal of organometallic chemistry》2006,691(23):5030-5037
Thermal substitution reaction of Cr(CO)4(η2:2-1,5-cyclooctadiene), Mo(CO)4(η2:2-norbornadiene), and W(CO)5(η2-bis(trimethylsilyl)ethyne) with N,N′-bis(ferrocenylmethylene)ethylenediamine (bfeda) yields M(CO)4(bfeda) complexes which could be isolated from the reaction solution and characterized by elemental analysis, MS, IR, and NMR spectroscopy. In the case of tungsten, W(CO)5(bfeda) is formed as intermediate and then undergoes the ring closure reaction yielding the ultimate product W(CO)4(bfeda). The electrochemical behavior of the M(CO)4(bfeda) complexes was studied by using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) in dichloromethane with tetrabutylammonium tetrafluoroborate as electrolyte. Constant potential electrolysis of the complexes was performed successively at their peak potentials at 0 °C in their CH2Cl2 solution and the electrolysis was followed by in situ recording the electronic absorption spectra in every 5 mC. In the electrolysis of Cr(CO)4(bfeda), the central Cr(0) is oxidized first and electrolysis continues with oxidations of two ferrocenyl groups until the end of totally three moles of electron passage per mole of complex. In the electrolysis of Mo(CO)4(bfeda) and W(CO)4(bfeda) the first oxidation occurs on the central atom forming a short-lived species which undergoes an intramolecular one-electron transfer and is reduced back to M(0) while one of the ferrocene units is oxidized to the ferrocenium cation at the same time. This indicates that the electron is transferred from iron to the central metal atom. 相似文献
78.
Jörg Fridgen Georg Eickerling Ana M. Santos 《Journal of organometallic chemistry》2004,689(17):2752-2761
Novel chiral 2′-pyridinyl alcohols derived from isopropylidene-protected carbohydrates are reported. They show different characteristics at the hydroxy group, but are all suitable ligands for chiral molybdenum(VI) complexes of the type MoO2L2 (L = chiral 2′-pyridinyl alcoholate). MoO2(acac)2 served as starting material in the complex syntheses. The structure of one ligand and one dioxo complex were exemplary established by X-ray crystallography. For catalytic runs in the enantioselective epoxidation catalysis trans-methylstyrene was used as model substrate, tert-butylhydroperoxide and cumolhydroperoxide, resp., as the oxidant. 相似文献
79.
Harry Adams Sarah A Morris Jeffrey C Motley 《Journal of organometallic chemistry》2004,689(3):522-527
Transfer of dithiolene ligands from [Ni(S2C2Ph2)2] to the dimolybdenum complex [Mo2(μ-C2R2)(CO)4Cp2] (R=CO2Me, Cp=η-C5H5) affords the first example of a dithiolene alkyne complex, [Mo2(μ-C2R2)(μ-S2C2Ph2)2Cp2], together with [Mo2(μ-SCRCR)(μ-SCPhCPh)Cp2] in which sulfur transfer from dithiolene to alkyne has occurred. 相似文献
80.
Enkhtsetseg Dashjav Guido Kreiner Walter Schnelle Frank R. Wagner Rüdiger Kniep 《无机化学与普通化学杂志》2004,630(5):689-696
Carbometalates: Complex Anions equation/tex2gif-stack-4.gif [MoC4/26—] in the Crystal Structure of Pr equation/tex2gif-stack-5.gif [MoIIC2] Criteria for the existence of carbometalates are established and discussed in a broader context. The concept is then applied to the novel compound Pr2[MoC2], which is characterized by chemical analyses, X‐ray diffraction and metallography. The crystal structure (tetragonal, P42/mnm, Z = 4, a = 581.29(8) pm, c = 1032.53(14) pm) consists of layered polyanions equation/tex2gif-stack-6.gif[MoC4/26—] of distorted vertex and edge sharing MoC4 tetrahedra. Praseodymium is also in a distorted tetrahedral coordination by carbon. The physical properties show “bad metal” behaviour and localized magnetic 4f‐moments in agreement with the existence of Pr3+‐species. A detailed bonding analysis using both the electron localization function ELF and the COHP method justifies the interpretation of the title compound as a carbomolybdate(II). 相似文献